click to enlarge
Noel T. Brewer, PhD, is a UNC Lineberger member and professor of health behavior at the UNC Gillings School of Global Public Health.

click to enlarge
Kurt Ribisl, PhD, is a professor of health behavior at the Gillings School and leader of the cancer prevention and control program at UNC Lineberger.

Affixing pictures on cigarette packs to illustrate the dangers of smoking increased attempts by smokers to quit, according to the findings of a study led by UNC Lineberger Comprehensive Cancer Center researchers published online June 6 by JAMA Internal Medicine.

Reducing smoking is a top public health priority because it is a leading cause of preventable death. While the 2009 Family Smoking Prevention and Tobacco Control Act requires pictorial warnings on cigarette packaging, implementation was stalled by a 2012 lawsuit filed by the tobacco industry.

The United States Court of Appeals for the District of Columbia Circuit ruled against nine pictorial warnings proposed by the U.S. Food and Drug Administration (FDA), saying the FDA had “not provided a shred of evidence” that the pictorial warnings reduce smoking.

Noel T. Brewer, PhD, a UNC Lineberger member and professor of health behavior at the UNC Gillings School of Global Public Health, worked with co-authors to address gaps in the research with a large randomized clinical trial. The investigators examined the effects on smoking behavior caused by adding pictorial warnings to the fronts and backs of cigarette packs.

The authors used four pictorial warnings that contained text required by the Tobacco Control Act and pictures illustrating the harms of smoking, which were selected from the FDA’s originally proposed set of images. In addition, they used four text-only warnings that contained U.S. Surgeon General warning statements that have been required on the side of cigarette packs since 1985.

The four-week trial included adult smokers in North Carolina and California. Of the 2,149 smokers enrolled in the study, 1,901 individuals completed it. Participants were randomly assigned to receive either text-only or pictorial warnings on their cigarette packs for four weeks, and research staff placed the warnings on cigarette packs that smokers brought with them when they attended weekly visits. Surveys were administered at the start of the study and at each visit.

The authors found that smokers whose cigarette packs had pictorial warnings were more likely to try to quit during the four week trial, with 40 percent of smokers in the pictorial warning group making a quit attempt compared with 34 percent in the text-only warning group (a relative increase of 18 percent).

Also, 5.7 percent of smokers who received pictorial warnings had quit smoking for at least a week by the end of the trial, compared with 3.8 percent of smokers who received text-only warnings (a 50 percent relative increase).

The authors note that the effects appear modest, but could have a substantial benefit across the population of U.S. smokers.

“This study provides the first evidence from an experimental study that pictorial warnings on cigarette packs are effective in promoting quit attempts and helping smokers to quit smoking,” said co-author Kurt Ribisl, PhD, professor of health behavior at the Gillings School and leader of the cancer prevention and control program at UNC Lineberger. “Countries that do not yet have pictorial warnings, such as the U.S., now have new evidence that should help their efforts to mandate pictorial warnings on all cigarette packs.”

Study limitations include: 1) not knowing what effects pictorial warnings may have over a longer period of time, and 2) participant self-selection possibly resulting in a study population with a greater interest in quitting smoking than the general population.

Study co-authors linked to the UNC Gillings School of Global Public Health include Brewer, Ribisl, and Marissa G. Hall, MSPH, doctoral candidate, all in the Department of Health Behavior, along with Humberto Parada, MPH, doctoral student of epidemiology, and Laura E. Bach, MSPH, alumna of the health behavior department and former project manager for the study. Seth Noar, PhD, professor in the UNC School of Media and Journalism and a UNC Lineberger member, also was a co-author.